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    <title>Document</title>
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    <script>
       /*  var arr = new Array();
        var arr1 = [];
        var arr2 = [1, 12.3, '好天气', true];

        console.log(arr, arr1, arr2); */

       /*  var arr = [];
        arr[0] = '武汉';
        arr[1] = '上海';
        arr[2] = '北京';
        arr[3] = '广州';
        arr[4] = '深圳';
        console.log(arr); */

        var arr = [1, 2, 3 , 4];
        arr[3] = '号';
        arr[0] = '蓝';
        arr[10] = '10=11 ';
        console.log(arr);
        console.log(arr[1]);
        console.log(arr[3]);
        console.log(arr[11]);
        console.log(arr[10]);
    </script>
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